Listen, my children, and I will tell you how to fix the infernal built-in jack on your Kubota ZD326.
The jack was one of the main reasons I wanted a Kubota. I figured it would make blade changes much easier. Then I bought a used Kubota with a jack that was nearly frozen.
No problem. I would just grease it later.
Today I finally got around to taking it apart, and I found out why it was frozen. When Kubota designed this thing, they included a generous serving of dumbass. I have to wonder if the engineer behind it is a descendant of Mr. Kubota himself. "What are we going to do with little Hiroshi? He failed out of Benihana school again!" "We call dad and get him a job at the company. Something unimportant."
To begin with, you take the jack off while the mower's deck is down. The is a little roll pin at the handle end, and you pound it out. At the other end, there is a thick pin that goes through the jack assembly, and incredibly, it is held in with a cotter pin. Pull the cotter pin, and the left end of the jack will be free.
I am replacing the cotter pin with a clevis pin. I don't know why Kubota didn't use a clevis pin. The jack is designed in a way that makes it highly likely it will have to be taken apart and serviced during the mower's life. A clevis pin comes right out, and you know what a pain big cotter pins are.
The jack handle is held on with a screw and nut. Pretty obvious.
The jack has three main parts: a dust shield that doesn't work, a screw that corrodes, and a nut that fills up with dirt. The shield is plastic, and for some reason it's held on with an internal retaining ring. The ring goes around the screw, like a ring on a piston. You pull, and the shield comes off. Putting the shield back on using the ring is not much fun, but it can be done.
The screw is plated with something that looks like cadmium, except where it wears against other parts without the much-needed bearing that Kubota didn't put in the design. That part is bare because friction removes the plating in a hurry. The bare area gets rusty, increasing the diameter and making the fit tight so the screw binds.
The dust shield does an excellent job of capturing dust and transferring it to the screw and nut. Once this occurs, it fills the threads and combines with your lubricant to form a coarse lapping compound that doubles as a thread locker.
Maybe Kubota designed this jack for impeccable Japanese lawns which are completely free of grit and sand because they are maintained by Japanese gardeners, but my American lawn, like many others, is full of bare spots, so this jack does not work well as designed. Sooner or later, it will lock up, necessitating the use of a floor jack or some other means of lifting the deck.
I disassembled the jack. I took the screw to the pedestal buffer and wire-wheeled most of the rust off. Then I went to a utility sink to clean the grit off the screw.
I used an amazing cleaning product: Aveeno Baby Daily Moisture Wash and Shampoo. This stuff is supposed to clean babies without drying their skin. My wife bought it for our son early this year, and in a short time, his skin felt like leather. It is possibly the harshest soap I have ever seen. It's like brake cleaner with a baby-fresh scent. It defats everything it touches.
We got different soap for the baby, but I kept the Aveeno for removing black grease from myself after I work on machinery. It's faster than mechanic's hand cleaner.
The Aveeno and a brush ripped the grease and dirt off the screw, and I used my wife's toothbrush on the nut. I haven't told her yet. It was a new one she hadn't opened, so I have time to replace it.
I greased the nut and screw with Super Lube and put the jack back together. I felt I had to do something to improve it, because I knew grit would start filling it up a week from today during the next mow.
I got a caulking gun and filled the open (left) end of the nut with silicone. I am letting it cure now. Once it cures, there will be a big rubbery plug blocking the once-open end of the jack. I may be wrong, but it looks like there is ample room for the plug. If not, I'll yank it out and try something else. It should greatly reduce dirt intrusion, and if it does, the jack will actually be useful.
I am also working on the left fuel tank. The mower stalls when I use it. The problem isn't the filters, pump, cap vent, or fuel lines, so I am cleaning the tank.
A helpful person said the tank was easy to take off and supplied information about removing the fender it sits under. Unfortunately, this information is not quite right.
You don't have to remove the fender to get the tank off, and that's a good thing, because you have to remove the step (floorboard) in order to get the fender off. The fender has a long tab that runs under the step. You have to remove a screw from the tab and pull the tab out from under the step. To do this, you have to get the step out of the way.
Fortunately, the fender can stay where it is. If you remove all the screws holding it on, you can lift it enough to get the tank out.
Unfortunately, the fuel hoses that have to be removed from the tank have death grips on the tank's nipples, and so far, I have not managed to get them loose. It is also necessary to remove several screws and take out the fuel sender, unless there is some way to detach the sender's wiring upstream. I have not found anything like that. I should cut the wires and make them detachable using plugs and receptacles.
In summary, the jack is a pretty good product for people with perfect lawns, but for the rest of us, it requires modification or frequent cleaning and lubrication.
The jack was one of the main reasons I wanted a Kubota. I figured it would make blade changes much easier. Then I bought a used Kubota with a jack that was nearly frozen.
No problem. I would just grease it later.
Today I finally got around to taking it apart, and I found out why it was frozen. When Kubota designed this thing, they included a generous serving of dumbass. I have to wonder if the engineer behind it is a descendant of Mr. Kubota himself. "What are we going to do with little Hiroshi? He failed out of Benihana school again!" "We call dad and get him a job at the company. Something unimportant."
To begin with, you take the jack off while the mower's deck is down. The is a little roll pin at the handle end, and you pound it out. At the other end, there is a thick pin that goes through the jack assembly, and incredibly, it is held in with a cotter pin. Pull the cotter pin, and the left end of the jack will be free.
I am replacing the cotter pin with a clevis pin. I don't know why Kubota didn't use a clevis pin. The jack is designed in a way that makes it highly likely it will have to be taken apart and serviced during the mower's life. A clevis pin comes right out, and you know what a pain big cotter pins are.
The jack handle is held on with a screw and nut. Pretty obvious.
The jack has three main parts: a dust shield that doesn't work, a screw that corrodes, and a nut that fills up with dirt. The shield is plastic, and for some reason it's held on with an internal retaining ring. The ring goes around the screw, like a ring on a piston. You pull, and the shield comes off. Putting the shield back on using the ring is not much fun, but it can be done.
The screw is plated with something that looks like cadmium, except where it wears against other parts without the much-needed bearing that Kubota didn't put in the design. That part is bare because friction removes the plating in a hurry. The bare area gets rusty, increasing the diameter and making the fit tight so the screw binds.
The dust shield does an excellent job of capturing dust and transferring it to the screw and nut. Once this occurs, it fills the threads and combines with your lubricant to form a coarse lapping compound that doubles as a thread locker.
Maybe Kubota designed this jack for impeccable Japanese lawns which are completely free of grit and sand because they are maintained by Japanese gardeners, but my American lawn, like many others, is full of bare spots, so this jack does not work well as designed. Sooner or later, it will lock up, necessitating the use of a floor jack or some other means of lifting the deck.
I disassembled the jack. I took the screw to the pedestal buffer and wire-wheeled most of the rust off. Then I went to a utility sink to clean the grit off the screw.
I used an amazing cleaning product: Aveeno Baby Daily Moisture Wash and Shampoo. This stuff is supposed to clean babies without drying their skin. My wife bought it for our son early this year, and in a short time, his skin felt like leather. It is possibly the harshest soap I have ever seen. It's like brake cleaner with a baby-fresh scent. It defats everything it touches.
We got different soap for the baby, but I kept the Aveeno for removing black grease from myself after I work on machinery. It's faster than mechanic's hand cleaner.
The Aveeno and a brush ripped the grease and dirt off the screw, and I used my wife's toothbrush on the nut. I haven't told her yet. It was a new one she hadn't opened, so I have time to replace it.
I greased the nut and screw with Super Lube and put the jack back together. I felt I had to do something to improve it, because I knew grit would start filling it up a week from today during the next mow.
I got a caulking gun and filled the open (left) end of the nut with silicone. I am letting it cure now. Once it cures, there will be a big rubbery plug blocking the once-open end of the jack. I may be wrong, but it looks like there is ample room for the plug. If not, I'll yank it out and try something else. It should greatly reduce dirt intrusion, and if it does, the jack will actually be useful.
I am also working on the left fuel tank. The mower stalls when I use it. The problem isn't the filters, pump, cap vent, or fuel lines, so I am cleaning the tank.
A helpful person said the tank was easy to take off and supplied information about removing the fender it sits under. Unfortunately, this information is not quite right.
You don't have to remove the fender to get the tank off, and that's a good thing, because you have to remove the step (floorboard) in order to get the fender off. The fender has a long tab that runs under the step. You have to remove a screw from the tab and pull the tab out from under the step. To do this, you have to get the step out of the way.
Fortunately, the fender can stay where it is. If you remove all the screws holding it on, you can lift it enough to get the tank out.
Unfortunately, the fuel hoses that have to be removed from the tank have death grips on the tank's nipples, and so far, I have not managed to get them loose. It is also necessary to remove several screws and take out the fuel sender, unless there is some way to detach the sender's wiring upstream. I have not found anything like that. I should cut the wires and make them detachable using plugs and receptacles.
In summary, the jack is a pretty good product for people with perfect lawns, but for the rest of us, it requires modification or frequent cleaning and lubrication.
